<br><font size=2 face="sans-serif">All of our OSS's are configured the
same. However on the first OSS which is experiencing the high CPU
load the number of io threads being started is much higher than the other
OSS servers.</font>
<br>
<br><font size=2 face="sans-serif">The server that is experiencing high
CPU</font>
<br>
<br><font size=2 face="sans-serif">ost.OSS.ost_io.threads_started=175</font>
<br>
<br><font size=2 face="sans-serif">Other OSS servers</font>
<br>
<br><font size=2 face="sans-serif">ost.OSS.ost_io.threads_started=128</font>
<br>
<br><font size=2 face="sans-serif">All off the OSS servers are configured
like this.</font>
<br>
<br><font size=2 face="sans-serif">ost.OSS.ost_io.threads_min=128</font>
<br><font size=2 face="sans-serif">ost.OSS.ost_io.threads_max=512</font>
<br>
<br><font size=2 face="sans-serif">Any direction/information to resolve
this issue is greatly appreciated. If any other info is needed please
let me know.</font>
<br>
<br>
<br>
<br><font size=2 face="sans-serif"><br>
Rocky</font>
<br>
<br>
<br>
<table width=100%>
<tr valign=top>
<td><font size=1 color=#5f5f5f face="sans-serif">From:</font>
<td><font size=1 face="sans-serif">Wang Yibin <wang.yibin@oracle.com></font>
<tr valign=top>
<td><font size=1 color=#5f5f5f face="sans-serif">To:</font>
<td><font size=1 face="sans-serif">Ronald K Long <rklong@usgs.gov></font>
<tr>
<td valign=top><font size=1 color=#5f5f5f face="sans-serif">Cc:</font>
<td><font size=1 face="sans-serif">lustre-discuss@lists.lustre.org</font>
<tr valign=top>
<td><font size=1 color=#5f5f5f face="sans-serif">Date:</font>
<td><font size=1 face="sans-serif">11/16/2010 09:54 AM</font>
<tr valign=top>
<td><font size=1 color=#5f5f5f face="sans-serif">Subject:</font>
<td><font size=1 face="sans-serif">Re: [Lustre-discuss] High CPU load,
only on 1 OSS</font></table>
<br>
<hr noshade>
<br>
<br>
<br><font size=3 face="sans-serif">Hello,</font>
<br>
<br><font size=3 face="sans-serif">Normally when stripe_offset is set to
-1, MDS will do load/space balancing automatically.</font>
<br><font size=3 face="sans-serif">What is your use pattern of the filesystem?</font>
<br><font size=3 face="sans-serif">It sounds like that your applications
are doing extensive I/O on that particular OSS.</font>
<br>
<br><font size=3 face="sans-serif">To find out why the load on the OSS
is so high, please </font>
<br><font size=3 face="sans-serif">- find what processes are hogging the
CPUs using top(1).</font>
<br><font size=3 face="sans-serif">- get the stripe info of your in-use
files to see whether most of them reside on the same OSS.</font>
<br>
<br><font size=3 face="sans-serif">If the files in use are not distributed
among the OSS servers, or your file usage pattern is one-OSS bound, you
may want to consider tuning the stripe_count/stripe_size.</font>
<br>
<br><font size=3 face="sans-serif"> 2010-11-1610:38 Ronald
K Long \u0434</font>
<br>
<br><font size=2 face="sans-serif"><br>
We recently setup a lustre config. 1 MDS 4 OSS's. Everything
is running fine except on the first OSS we are experiencing very high cpu
load. The first OSS is running a CPU load in the high 50's. The
other 3 OSS's are steady at around 8. Everything is the same between
all of the OSS's.</font><font size=3 face="sans-serif"> <br>
</font><font size=2 face="sans-serif"><br>
The stripe is setup </font><font size=3 face="sans-serif"><br>
</font><font size=2 face="sans-serif"><br>
stripe_count: 1 stripe_offset: -1</font><font size=3 face="sans-serif">
<br>
</font><font size=2 face="sans-serif"><br>
Red Hat 5 64bit</font><font size=3 face="sans-serif"> <br>
</font><font size=2 face="sans-serif"><br>
kernel-2.6.18-194.3.1.el5_lustre.1.8.4</font><font size=3 face="sans-serif">
</font><font size=2 face="sans-serif"><br>
kernel-devel-2.6.18-194.3.1.el5_lustre.1.8.4</font><font size=3 face="sans-serif">
</font><font size=2 face="sans-serif"><br>
lustre-ldiskfs-3.1.3-2.6.18_194.3.1.el5_lustre.1.8.4</font><font size=3 face="sans-serif">
</font><font size=2 face="sans-serif"><br>
lustre-1.8.4-2.6.18_194.3.1.el5_lustre.1.8.4</font><font size=3 face="sans-serif">
</font><font size=2 face="sans-serif"><br>
lustre-modules-1.8.4-2.6.18_194.3.1.el5_lustre.1.8.4</font><font size=3 face="sans-serif">
<br>
<br>
</font><font size=2 face="sans-serif"><br>
Any thing I can check on the problem OSS to rectify this issue.</font><font size=3 face="sans-serif">
<br>
</font><font size=2 face="sans-serif"><br>
Thank you in advance</font><font size=3 face="sans-serif"><br>
</font><font size=2 face="sans-serif"><br>
Rocky </font><font size=3 face="sans-serif"><br>
_______________________________________________<br>
Lustre-discuss mailing list</font><font size=3 color=blue face="sans-serif"><u><br>
</u></font><a href="mailto:Lustre-discuss@lists.lustre.org"><font size=3 color=blue face="sans-serif"><u>Lustre-discuss@lists.lustre.org</u></font></a><font size=3 face="sans-serif"><br>
</font><a href="http://lists.lustre.org/mailman/listinfo/lustre-discuss"><font size=3 face="sans-serif">http://lists.lustre.org/mailman/listinfo/lustre-discuss</font></a>
<br>
<br>
<br>